Latitudinalandbathymetricpatternsinthedistributionandabundance of mesopelagicfishintheScotiaSea

• Published in: Deep Sea Research Part II: Topical Studies in Oceanography
• Main Authors: Collins, Martin A., Stowasser, Gabriele, Fielding, Sophie, Shreeve, Rachel, Xavier, José C., Venables, Hugh J., Enderlein, Peter, Cherel, Yves, van de Putte, Anton
• Other Authors: British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Oceanlab, Aberdeen University, Institut Marine Research, University of Coimbra Portugal (UC), Centre d'Études Biologiques de Chizé (CEBC), Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS), Laboratory of Animal Diversity and Systematics, Catholic University of Leuven = Katholieke Universiteit Leuven (KU Leuven)-Institut Royal des Sciences Naturelles de Belgique = Royal Belgian Institute of Natural Sciences (IRSNB / RBINS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2012
• Subjects: Myctophid; Myctophidae; Bathylagidae; Biomass; Southern Ocean; [SDE]Environmental Sciences; Antarc*
• Online Access: https://hal.science/hal-00662416; https://doi.org/10.1016/j.dsr2.2011.07.003

International audience Mesopelagicfishareakeycomponentofthepelagicecosystemthroughouttheworld'soceans.Opening and closingnetswereusedtoinvestigatepatternsinthedistributionandabundanceofmesopelagic fish fromthesurfaceto1000monaseriesoftransectsacrosstheScotiaSeafromtheice-edgetothe AntarcticPolarFront.Atotalof141non-targetnethaulswereundertakenduringthreecruises(Nov 2006, Jan2008andMar2009),with7852teleostfishcaptured,representing43speciesin17families.A further 1517fishwerecaughtintargetednethauls.ThedominantfamiliesweretheMyctophidae (6961 specimens;21species)andBathylagidae(1467specimens;4species).Fewfishwerecaughtin the upper400mduringdaylight,whichwasattributedtoacombinationofnetavoidanceanddiurnal verticalmigration.Speciescompositionwaslinkedtodepthandlocationandwascloselyassociated with oceanographicfeatures.Diversitywaslowestincoldwateratthemostsoutherlystations,which were dominatedby Electronaantarctica, Gymnoscopelusbraueri and Bathylagusantarcticus. Further north,diversityincreasedwiththeadditionofspeciessuchas Krefftichthysanderssoni, Protomyctophum bolini and Electronacarlsbergi. Thedepthintegratedbiomassofmyctophidswassimilaracrossthe latitudinaltransectandproducedanestimateof4.5milliontonnesintheScotiaSea.Bathylagidswere patchily distributed,butwereabundantinthelowermesopelagiczone(4400 m)andarepotentially significantzooplanktonconsumers.Giventhebiomassofthemyctophidsandbathylagidscoupledwith the verticalmigrationsofmanyspecies,thesefisharelikelytoplayasignificantroleincarbonexport from thesurfacewaterstothedeepocean.